The present invention relates generally to a small firearm having a firing pin mounted in a moveable slide mechanism. More specifically, the present invention relates to a device for controlling the position of the firing pin relative to the slide mechanism in preparation for firing of the firearm.
On many automatic small firearms a slide mechanism is mounted within a housing of the firearm. The slide mechanism is shiftable between a forward or closed in which a cartridge is properly position for firing, and a retracted position. Movement between these two positions both allows for the ejection of a spent cartridge and the positioning of a fresh cartridge in the breech for firing. As is known, a hammer advances in response to operation of a trigger and strikes the rear end of a firing pin.
Typically, the firing pin is mounted to the slide assembly. A firing pin spring bears against the slide assembly and biases the firing pin rearwardly so that a rear end of the firing pin protrudes from the slide assembly, with the rear end of the firing pin protruding slightly from the slide. When the firing pin is so positioned, a front end of the firing pin is retracted away from a front end of the slide assembly. When the hammer strikes the rear end of the firing pin, the pin is accelerated in a forward direction against the force of the firing pin spring. The percussion cap of the cartridge is disposed adjacent the percussion plate at the front end of the slide assembly. Consequently, the front end or tip of the firing pin emerges from the front end of the slide so that the tip of the firing pin strikes the percussion cap of the cartridge, thus firing the firearm.
In order to prevent firing of the cartridge before the slide assembly is fully closed, a blocking assembly may be provided for preventing contact between the hammer and the firing pin until the slide assembly has reached its fully closed position. Typically, during regular or continuous firing, prior art blocking mechanisms cooperate with the trigger and act by preventing the trigger from releasing the hammer unless the slide is in the proper fully closed positions. Such blocking mechanisms are controlled by the position of the slide, so that, at least in principle, firing of the forearm is only possible when the slide is fully closed.
However, manufacturing tolerances, soiling and/or wear on the blocking mechanism or failure of a component can cause a situation in which, despite the blocking mechanism, the trigger causes release of the hammer when the slide is still open or unlocked or only partially locked. In general, experience has shown that prior art devices designed to prevent premature firing of a cartridge are not adequately reliable for a variety of reasons.
In accordance with an aspect of the invention, a small arm having a trigger operatively engaging a releasable hammer includes a housing including a fixed part, a slide disposed in the housing and having a rear end, with the slide being moveable between an open position and a closed position, a firing pin mounted to the slide and being moveable relative to the slide along a linear path between a partially retracted position in which a rear end of the firing pin is disposed to prevent contact with the hammer and a fully retracted position in which the rear end of the firing pin is disposed to permit contact with the hammer, the firing pin further being adapted to move to a firing position in response to impact of the hammer against the rear end of the firing pin, and a firing pin control assembly. The firing pin control assembly includes a spring biased sleeve slidably receiving the firing pin, with the sleeve being moveable between a forward position in which the sleeve moves the firing pin to the partially retracted position and a rearward position in which the sleeve moves the firing pin to the fully retracted position. The sleeve is moveable to the rearward position in response to forward movement of the slide to thereby maintain the firing pin in the partially retracted position until the slide is disposed in the closed position.
In further accordance with a preferred embodiment, the firing pin includes a spring positioned to apply a rearward biasing force to the firing pin, and further including a counterspring disposed to apply a forward biasing force to the sleeve, and wherein the counterspring has a spring constant greater than a spring constant of the firing pin spring. Preferably, the sleeve includes a lateral protrusion positioned to contact the fixed housing part in response to movement of the slide toward the forward position, thereby shifting the firing pin to the fully retracted position as the sleeve shifts from the forward position to the rearward position.
The rear end of the firing pin may be disposed within the slide when the firing pin is in the partially retracted position, and further the rear end of the firing pin may protrude from the rear end of the slide when the firing pin is in the fully retracted position. The fixed housing part may include a rearward face, with the rearward face being positioned to engage a lateral protrusion on the sleeve as the slide moves toward the closed position, thereby shifting the sleeve to the rearward position. The fixed housing part may include a forward face adapted to eject a cartridge in response to rearward movement of the slide. Further, the firing pin may include a safety ring abutting a forward portion of the sleeve, with the safety ring limiting rearward movement of the firing pin relative to the sleeve.
A second sleeve may be fixed to the slide with the second sleeve slidably receiving the firing pin. The counterspring may be disposed between the first and second sleeves for applying a forward biasing force to the first sleeve. The second sleeve may further positioned to limit the rearward movement of the first sleeve, and including a shoulder defined in the slide to limit the forward movement of the first sleeve, with the safety ring abutting cooperating portions of the first sleeve and the firing pin to limit rearward movement of the firing pin relative to the first sleeve.
According to another aspect of the invention, a small firearm having a firing pin control device comprises a hammer responsive to operation of a trigger, a housing, a slide assembly slidably disposed in the housing and moveable between a closed position and an open position, a firing pin mounted to the slide and being moveable relative to the slide along a linear path between a first position in which contact between a rear end of the firing pin and the hammer is prevented, and a second position in which contact between the rear end of the firing pin and the hammer is permitted, a firing pin spring positioned to apply a rearward biasing force to the firing pin, a forward sleeve slidably mounted to the slide and being moveable relative to the slide between a forward position and a rearward position, with the sleeve including a bore sized to slidably receive the firing pin therethrough, the sleeve further including a protrusion, a retaining sleeve mounted to the slide, and a counterspring engaging the forward sleeve and the retaining sleeve and being arranged to apply a forward biasing force to the sleeve thereby urging the forward sleeve toward the forward position. Accordingly, in response to movement of the slide toward the closed position the lateral protrusion contacts the fixed part of the housing thereby moving the forward sleeve toward the rearward position, so that the rear end of the firing pin is moved from the first position to the second position.
According to a further aspect of the invention, the small arm includes a hammer, a housing including a fixed part, a slide disposed in the housing, with the slide being moveable between an open position and a closed position, and a firing pin mounted to the slide and being moveable relative to the slide along a linear path between a first position in which contact between the firing pin and the hammer is prevented and a second position in which contact between the firing pin and the hammer is permitted. The firing pin control assembly includes a pair of sleeves mounted in the slide, with the firing pin being slidable relative to the sleeves. A forward one of the sleeves engages the firing pin and is moveable between a forward position in which the firing pin is disposed in the first position and a rearward position in which the firing pin is disposed in the second position. The firing pin control assembly includes a counterspring arranged to bias the forward sleeve toward the forward position. A portion of the sleeve cooperates with the fixed housing part to thereby move the firing pin to the second position in response to movement of the slide to the closed position.